London has been battered by 50mph winds that have felled trees and caused travel chaos. Powerful gusts swept across the capital as the Met Office issued a yellow "be aware" weather alert for most of the country.

A former top mandarin has hit out at ministers for "dumping on" civil servants and holding them in contempt.

Some politicians such as Francis Maude, who has been pushing through controversial Whitehall reforms, do not understand the meaning of leadership, ex-Cabinet secretary Lord Butler of Brockwell said.

The comments, made in an interview with BBC Radio 4's Week In Westminster, emerged with tensions running high between ministers and mandarins.

The peer pointed to recent remarks by Mr Maude, the Cabinet Office minister, insisting that civil servants need to "speak truth to power".

Lord Butler said: "I agree with that but people are not encouraged to speak truth to power when in the same breath in the same interview they are told that they will be dumped on when things go wrong.

"I'm sorry to say, I really think that Mr Maude and some of his colleagues don't understand leadership.

"My view is that the relationship between ministers and the civil service works best when they work together in a mutually supportive relationship, with loyalty on both sides. And backstairs sniping, whichever side it comes from, shows that something is wrong and there's been too much of that backstairs sniping."

Lord Butler, who served under Margaret Thatcher, John Major and Tony Blair, said there is "backstairs sniping" against civil servants in the media "almost every single day".

He said: "I think there are several examples. There's been criticism of individual civil servants. I don't know where it comes from. Robert Devereux, the Permanent Secretary of the Department of Work and Pensions who has been criticised about the difficulties of universal credit. There was briefing against Sir Bob Kerslake, the head of the civil service.

"Again, I don't know where it comes from. But this sort of thing is a sign that something is quite seriously wrong."

Asked if he thinks such briefings come from within the Cabinet Office, the peer replied: "I've no idea. I mean, how can you tell where these things come from? But wherever they come from, they are wrong."

Lord Butler dismissed as "nonsense" the idea that senior civil servants are not held accountable for failures in big projects.

"Reform of the civil service isn't new. It's been going on for 40 or 50 years and more is needed," he said.

"But my point is that it is best achieved by leadership and by driving and by showing esteem for the civil service and not by backstairs sniping which shows contempt for the civil service."

Lord Butler voiced caution about recently announced plans to allow ministers to make around 10 personal appointments to their private offices.

"I'm for ministers having all the help that they need, whatever source it comes from, subject to two points," he said.

"First of all, it mustn't be an excuse for giving political cronies jobs at public expense and, secondly, they shouldn't be a cocoon that protects the minister and pours poison into the ears of the minister about the civil service."

:: The Week In Westminster is on BBC Radio 4 at 11am.

A spokesman for Mr Maude said: "The Civil Service has brilliant people but somehow ends up being less than the sum of its parts, because of a hierarchical system and a rigid culture. It's not right to patronise and infantilise people by pretending that everything is perfect in the best of all possible worlds.

"Good leadership is not about sweeping problems under the carpet. Francis and the leadership of the Civil Service have highlighted issues which need to be addressed. The same issues are raised in a survey of 200,000 civil servants.

"We owe it to the taxpayer, users of public services, and civil servants themselves to address these issues in an honest and truthful way. That's just what we are doing".

"What Francis said was that 'everybody has to take responsibility for what they were part of' - that's axiomatic and the alternative is no responsibility and no accountability."